Bidessonotus melanocephalus Regimbart , 1895

Miller, Kelly B., 2016, New species of Bidessonotus Regimbart, 1895 with a review of the South American species (Coleoptera, Adephaga, Dytiscidae, Hydroporinae, Bidessini), ZooKeys 622, pp. 95-127 : 109-110

Taxon classification Animalia Coleoptera Dytiscidae

Bidessonotus melanocephalus Regimbart, 1895 Figs 21, 34

Bidessonotus melanocephalus Régimbart, 1895: 332; J. Balfour-Browne 1947: 443; Young 1969: 2; 1990: 375; Biström 1988: 18; Nilsson 2016: 99.

Bidessus (Bidessonotus) melanocephalus , Zimmermann 1920: 62.

Bidessus melanocephalus , Blackwelder 1944: 76.

Diagnosis.

Specimens of Bidessonotus melanocephalus are darkly colored with the posterior surface of the head and the ventral surfaces dark brown. The prosternal process is lanceolate but not sulcate. The apical blade of the male median lobe is very broad with very well developed apicoventral and apicodorsal teeth and a broad tooth near the medial end of the proximal margin (Fig. 21a,d). The right lateral lobe has the apical segment apically broadly rounded and expanded along the ventral margin (Fig. 21b). The apical segment of the left lateral lobe is short, broad and curve and distinctly pointed along the dorsal margin (Fig. 21c).

Discussion.

Young (1990) compared this species with Bidessonotus inconspicuus . This is one of only a couple Bidessonotus species known from central and southern South America.

Distribution.

Known from Brazil and Peru (Fig. 34, Young 1990).